The purpose of this program project grant is to investigate the biology and improve transplantation in clinical malignancy, syngeneic, and autologous marrow transplantation in clinical malignancy, diseases of marrow failure and in certain genetic diseases. The proposal is made up of five projects: 1. Preparative Regimens and Anti- Tumor Trials. This project is designed to investigate new preparative regimens in various hematological malignancies and methods of "purging" marrow for autologous transplantation in acute lymphocytic leukemia. 2.Graft-versus-Host Reaction and Disease. The aims of this project are to investigate the basic mechanisms involved and therapeutic prevention and treatment of Graft-versus-Host Disease. 4. Pharmacology in Bone Marrow Transplantation. The purpose of this project is to provide knowledge as to the pharmacokinetics and mechanism of agents employed in preparative regimens, in vitro purging of tumor cells, and agents used to prevent and treat graft-versus-host disease. 5. Biology and viral and other Infections in Bone Marrow Transplantation. the purpose of this project is to better define the biologic mechanisms and develop strategies for the preventional and therapy of viral and other infections. 6. Core components. This project represents the core of the program and includes administrative and support services, cytogenetics and RFLP analysis, statistics and data, stem cell laboratory, pathology and outpatient services.